Another streamlet 3 m. wide flowed into the Arinos from the north-east on the right bank. The main river there was of a width of 400 m.
Another great island—Luiz Schnoor Island—also most beautiful, like the others, was next seen. We halted on it for our midday meal, and to take the usual astronomical observations. The sky had, by that time, become beautifully clear, of a dense cobalt blue, and I was able to take twenty-three sights of the sun. I generally took a great many sights with the sextant and artificial horizon, in order to define the latitude and longitude with greater accuracy. We were then in lat. 11° 38′·4 S.; long. 57° 35′ W.
Gorgeous gamelleira or figueira trees (ficus) were to be seen on that island, standing high up upon arches formed by vigorous roots. In a way the lower part of those figueiras resembled a huge octopus, the branches being extremely contorted as they clung to the ground in order to support the weight of the giant tree of which they made part. One could easily walk under the tree among the roots and still have six or eight feet of space left above one's head.
As I went round to explore the island while my men were cooking the dinner, I discovered a small lake in the centre of the island—a most poetic spot, with its neat, delightful vegetation all round it reflected as in a mirror in the golden waters which reproduced in a deeper tone the rich sunset tints of the sky above. I sat myself down to look at the beautiful scene. The poetry vanished at once. There were millions of ants which swarmed all over me the moment I sat down upon the ground, and bit me with such fury that I had to remove my clothes in the greatest haste and jump into the water. That raised a cloud of mosquitoes, which made it most uncomfortable for me when I came out again and was busy searching for ants in my clothes.
My men killed a beautiful long-armed spider monkey. I was sorry, as I had watched the wonderful jumps of this animal from one tree to another. Using the impetus of the swing which they could obtain from the immense length of their arms, as well as the swing of the branch on which they were hanging, they could fly enormous distances through the air. The span from hand to hand in proportion to the size of the body was really amazing.
Luiz Schnoor Island was 450 m. long. Plenty of rubber trees were to be seen on the right bank of the river after passing this great island, especially where the river described a large sweeping curve towards the north-east.
Farther on, close to the right bank, an island 100 m. long and 5 ft. high, of yellow sand and gravel, showed brilliantly with its vivid colouring upon the blue waters of the river. For identification' sake I named it Gravel Island on the map I was making of the river. I seemed to be in fairyland—but for the company of my men—as I floated down the stream, there 400 m. wide.
We had gone hardly 4 kil. when we came to another ideal island—Margherita Island—400 m. long and 200 m. wide, with magnificent trees upon it. A small stream joined the Arinos on the left side. Lower down stream we had thin forest on both sides, with some remarkable oleo trees, with their minute grey leaves and the branches, laden with red berries, drooping—weeping-willow-like—right down in the water.
Next we came to sand and gravel banks with islets 1 ft. high emerging from the water in the centre of the river, all those little islets displaying verdant grass on their southern side and pure white sand on the northern side.
The river was at that point flowing in a N.N.E. direction. Then came a long straight line of 6,000 m. of river flowing to 305° b.m. About half-way through this long stretch the stream divided into two large arms, one in direct continuation of the above bearings, the other in a curve, encircling an island 1,000 m. broad. The basin—as still as a lake—in which this island was situated was not less than 1,500 m. across. The island—Charles Landor Island—was 2,000 m. in length. It had plenty of rubber trees upon it, and plenty were to be seen also on the banks. We went some 8 or 10 kil. farther that night, and at five o'clock we halted, having made poor progress that day—only 60 kil.